Foundry molding machine and method of molding



L. F. MlLLER 3,

FOUNDRY MOLDING MACHINE AND METHOD OF MOLDING Feb. 9, 1965 5Sheets-Sheet 1 Filed July 9, 1958 INVENTOR.

LEON F. MlLLER UMWF'BEMMQ/ ATTORNEYS L. F. MILLER 3,163,754

FOUNDRY MOLDING MACHINE AND METHOD OF MOLDING Feb. 9, 1965 5Sheets-Sheet 2 Filed July 9, 1958 m 3 @N R. O m w n f m M 5 m E F. .L IhLHP I I WH I I I 1" N ,P L MUHM MH UUWMK x 0 I I HW I L I I h WH I HH II HWH HH .vm E L my 5 I j i .0 WW 1 LL i n w .m B n .w n 0 u 5 i QATTORNEYS Feb. 9, 1965 L. F. MILLER 3,168,764

FOUNDRY MOLDING MACHINE AND METHOD OF MOLDING Filed July 9, 1958 5Sheets-Sheet 3 O as INVENTOR. LEON F. MILLER BY (71mm (WM ATTORNEYS Feb.9, 1965 F. MILLER 3,163,764

FOUNDRY MOLDING MACHINE AND METHOD OF MOLDING Filed July 9, 1958 5Sheets-Sheet 4 INVENTOR.

LEON F'. MILLER ATTORNEYS Feb. 9, 1965 F. MILLER 3,168,764

FOUNDRY MOLDING MACHINE AND METHOD OF MOLDING Filed July 1958 5Sheets-Sheet s INVENTOR. LEON F. MILLER ATTORNEYS United States PatentOffice 3,168,764 Patented Feb. 9, 1965 3,168,764 FOUNDRY MULDWG MACHINEAND METHOD OF MQLDHNG Leon F. Miller, Rocky River, Ohio, assignor to TheOsborn Manufacturing Qompany, Cleveland, Ohio, at corporation of OhioFiled July 9, 1958, Ser. No. 747,474 43 Claims. (Cl. 2236) Thisinvention relates as indicated to a foundry molding machine and methodof molding, and more particularly to a machine and method utilizing asqueezing operation to squeeze the sand or other molding materialagainst an appropriate pattern.

A well-known method of producing foundry molds is the so-calledjolt-squeeze method, the sand being compacted against the pattern bymeans of a violent jolting operation followed by imposition of heavysqueezing pressure. lolting has proved advantageous in effectivelycompacting the sand against the different surfaces of the pattern buthas been found very objectionable in other respects. it is an extremelynoisy, indeed deafening, operation and requires the provision of amassive foundation for the machine and relatively heavy construction ofthe machine itself. it is accordingly an important object of the presentinvention to provide a molding apparatus and method whereby high qualityfoundry molds may be produced without the necessity of employing ajolting operation.

While a simple squeeze operation may be adequate in certain cases wheresimple shallow patterns are employed, it has not been found adequateproperly uniformly to compact the sand against the various facets of arelatively deep and complex pattern, the squeezing pressure beingimposed in one direction only. It is therefore another important objectof my invention to provide an apparatus and method of molding involvingthe application of squeezing pressure in a plurality of directions.

Still another object is to provide a novel foundry flask suitable forhandling in the usual manner and yet adapted for use in such multiplesqueeze operation.

A further object is to provide such flask of a form which willfacilitate shake-out following the casting operation and which may beformed to correspond generally to the shape of the pattern employed soas to reduce the quantity of molding sand required and permit improvedramming of the sand against the pattern.

Other objects of the invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said inventionthen comprises the features hereinafter fully described and particularlypointed out in the claims, the following description and the annexeddrawing setting forth in detail certain illustrative embodiments of theinvention, these being indicative, however, of but a few of the variousways in which the principle of the invention may be employed.

In said annexe/.1 drawing:

FIG. 1 is a semi-diagrammatic front elevational view of one form ofapparatus embodying the principles of my invention;

FIG. 2 is a side elevation of the apparatus of FIG. 1;

FIG. 3 is a front view of the flask-enclosing girdle frame ready forperformance of the squeeze operation;

FIG. 4 is an end view of the flask-enclosing girdle frame illustratingthe manner of performing such squeeze operation;

PK}. 5 is a top plan view of the FIGS. 3 and 4 assembly, including thesuperimposed squeeze board;

FIG. 6 is an enlarged fragmentary horizontal crosssection taken on theline 66 on FIG. 3 showing the arrangement of the squeeze diaphragm andflask;

FIG. 7 is a vertical cross-section through the flask-enclosing girdleincluding adapter means for employment of a blowing machine to fill theflask and modified inflatable squeeze means;

FIG. 8 is a similar vertical cross-section showing a further modifiedflask-enclosing girdle and inflatable diaphragm squeeze means;

FIG. 9 is a vertical section through still another modifiedflask-enclosing girdle and blow machine assembly including provision forsupplemental elevation of the flask and girdle following performance ofthe blowing operation;

PEG. 10 is a vertical section corresponding to FIG. 9 but showing theflask thus elevated and the lateral squeeze diaphragrns inflated;

FIGS. 11, 12 and 13 are a side elevation, an end elevation, and a topplan view respectively of a novel flask embodying tr e principles of myinvention; and

FIG. 14 is a transverse section taken on the line 1 l-14 on PEG. 13through one of the flask bars to show the configuration of the same.

General construction Referring now to FIGS. 1 and 2 of the drawing, theembodiment of my invention there illustrated comprises a base frame 1carrying two vertically extending side frame members 2 and 3, theselatter supporting horizontal rails a and 5 with rollers 6 and 7 on whichhead frame 3 is adapted to be reciprocated into and out of positionbeneath sand bin 9 through operation of actuating cy inders 1d and it)carried by outrigger brackets 11 and 12. Through a linkage arrangement(not shown) the clamshell gates 13 and 14 may be caused to open whenhead frame 8 is reciprocated from beneath the same and closed when suchhead frame is returned to the position shown in the drawing. The upperend portions of side frames 2 and 3 are turned in to prevent lifting ofhead frame 8 when in such position. A squeeze board 15 is mounted on theunder side of head 8 and carries a number of downwardly projectingsqueeze biscuits 16 adapted to enter a flask to compact the sandtherewithin.

Base frame 1 is adapted to rest upon the foundry floor and includes alarge centrally located squeeze cylinder 17 projecting downwardly belowfloor level and containing a squeeze piston 18 adapted to be elevated bymeans of fluid pressure in well-known manner. Such piston carries asqueeze table 19 having upwardly projecting register pins 2% and 21 andadapted to support the pattern P thereon. A flask F is supported abovetable 19 on horizontal roller conveyors 22 and 23 and its horizontalperipheral flange 24 is provided with apertures 25 and 26 adapted toregister with tapered pins 20 and 21 when table 19 is elevated throughactuation of piston-cylinder assembly 18, 1'7. Flask F is of specialconstruction as explained more in detail below.

A downwardly outwardly tapered girdle frame 27 is supported above flaskF on brackets 28 and 29 projecting inwardly from side frame members 2and .3 respectively and is mounted for vertical reciprocation on guidepins 30 and 31. An upset frame portion 32 of slightly smaller dimensionsextends upwardly from the top of girdle 27.

General operation The remaining elements of the machine structure maybest be described in conjunction with an explanation of the generaloperation of the machine.

An appropriate pattern P is mounted on squeeze table 19 and a specialgrid type flask F is rolled into position on roller conveyor 22, 23.Fluid pressure piston-cylinder assembly 18, 17 is energized to elevatesqueeze table 19 to pick up flask F and to carry the latter upwardlyuntil peripheral flange 24 engages the lower edge of girdle 27.

Head frame 8 is reciprocated out of position beneath sand bin 9 and sandis now discharged from such bin into girdle 27 filling upset frameportion 32 to the proper level. The squeeze head is now reciprocatedinto position above the upset frame so that the various parts arearranged as shown in FIGS. 3, 4 and 5. Then, as indicated in dotted linein FIG. 4, piston-cylinder assembly 18, 17 will be actuated further toelevate table 19 to cause squeeze biscuits 16 to enter upset frame 32and project downwardly between the grid bars of flask F, compacting thesand against pattern P and more particularly against the upwardlydisposed surfaces of such pattern. Simultaneously with the performanceof such mechanical squeezing operation or lagging slightly thereafter,fluid pressure (ordinarily pneumatic but hydraulic fluid may be utilizedif desired) is admitted through inlet 33 in girdle 27 to force flexiblediaphragm 34 from its outward position as indicated in FIGS. 3 and 4 tothe inner position indicated at the right-hand side of FIG. 4. Suchdiaphragm may be of rubber or other resiliently distensible material orit may be of rubber or Neoprene impregnated fabric which is flexible butnot truly distensible. As indicated in FIGS. 3 and 4 but more clearlyshown in enlarged section in FIG. 6, the upper and lower edges of thediaphragm 34 may be clamped in sealing engagement with the upper andlower portions of girdle 27 by means of clamp bars such as 35 and screws36, the diaphragm extending completely around the inner periphery ofgirdle 27 and in effect forming a liner therefor.

The flask F is formed in this case of a rectangular base member 37secured to the horizontal peripheral flange 24 and having welded theretothe arched grid members 38 so that the flask to some extent resembles aninverted openwork basket. Such members 38 form a grid through the spacesof which the squeeze biscuits 16 are adapted to extend, and such members38 are of relatively narrow cross-section with their longer sectionsextending toward the diaphragm and girdle. Consequently, when suchdiaphragm is forced inwardly, relatively little resistance is affordedby members 38 to the lateral compacting of the sand against pattern Pthrough such action of the diaphragm. Furthermore, there is very littlestrain on the flask during performance of the two types of squeezingoperations.

Upon completion of such squeezing operations, the fluid pressure isrelieved behind diaphragm 34 and the fluid preferably positivelywithdrawn so as to move such diaphragm into fully retracted position.Piston-cylinder assembly 18, 17 is then actuated to lower squeeze table19, thereby first depositing girdle 27 on the supporting brackets 28 and29 and then withdrawing flask F from such girdle and depositing it onits roller conveyor 22, 23. Continued downward movement of the squeezetable then serves to draw the pattern from the mold within the flask,and the flask and mold may be removed from the machine on conveyor 22,23. The cycle is then ready to be repeated.

Modifications utilizing'blow filling .Now referring to FIG. 7 of thedrawing, a somewhat modified construction is there illustrated whereinthe flask and girdle are adapted to be filled through employment of ablowing operation comparable to that utilized in conventional coreblowing machines.

Reference may be had to Ellms Patent No. 2,545,944 wherein is discloseda core blowing machine suitable for employment for my purpose. Otherforms of commercially available core blowing machines well known in theart may likewise be employed.

In the embodiment illustrated in FIG. 7, the lower end of the coreblower sand reservoir 39 is provided with an adapter 40 including acentral downwardly tapering portion 41 forming the lower end of thereservoir and terminating in blow hole 42. A downwardly projectingperipheral flange 43 is provided with a clamping ring 44 to secure theouter peripheral edge of a flexible annular diaphragm 45. The innerperipheral edge of such diaphragm is secured about blow hole 42 byclamping ring 46. The upper edge of girdle 27 is adapted to mate insealing engagement with such clamping ring 44, and ring 44 also has anumber of screened vent openings 47 in the manner of core boxes forescape of air therethrough during performance of the blowing operation.The flask encircling diaphragm 34 is shown in solid line in deflatedposition and in dotted line in inflated position. Upper annulardiaphragm 45 is likewise shown in solid line in deflated or retractedposition and in dotted line in inflated or expanded position, fluidbeing admitted under pressure through inlet 48 in adapter 40 thus toexpand such latter diaphragm.

As described above, the squeeze table 19 is elevated through action ofpiston-cylinder assembly 18, 17 to pick up the flask F and then thegirdle 27 which is elevated and held in tight fitting engagement withblow machine adapter 49. The flask and girdle are then filled with sandblown through orifice 42 in conventional manner with the diaphragms inretracted position. Upon conclusion of the blow, such diaphragms 34 and45 are inflated further to compact the sand against the lateral andupper surfaces of the pattern. Such diaphragrns are now preferablyretracted to solid line position and table 19 lowered first to disengagethe girdle 27 from the blowing machine adapter, then to withdraw theflask and mold from the girdle, and finally to draw the pattern P fromthe finished mold.

In the embodiment shown in FIG. 8 of the drawing, the apparatus isgenerally similar to that of FIG. 7 except that the adapter and girdlecomprise a single unit attached to the reservoir 39 of the blowingmachine and but a single diaphragm 49 need be utilized. Such combinedadapter and girdle comprises a downwardly opening box 50 having a fluidpressure inlet 51 and a central blow inlet 52. The diaphragm 49 extendsaround the inner periphery of the box, being clamped in sealingengagement therewith adjacent its lower edge and secured at its upperedge somewhat radially outwardly spaced from blow inlet 52, affordingroom for screened vent openings such as 53 and 54 surrounding such blowopening. Consequently, diaphragm 49 not only laterally encompasses flaskF but also overlies the upper portion of the flask to a considerableextent.

As previously explained, squeeze table 19 is elevated first to pick upflask F and then to carry such flask into box 50 where its lower flange24 is clamped in sealing engagement as shown. The blowing machine isoperated to blow sand through opening 52 to fill the flask and box withthe diaphragm 49 being in solid line position. Such blowing operation iseffective to compact the sand quite satisfactorily against the upperportions of the pattern more or less beneath the blow opening, butfurther compacting of the sand is desired against other portions of thepattern. This is effected by admitting fluid pressure through inlet 51to force diaphragm 49 inwardly substantially into dotted line positionindicated. The arched frame members 38 of flask F may be provided withaligned orifices such as 55 into certain of which rods such as 56 may beinserted, assisting in supporting the finished mold. Upon conclusion ofthis squeezing operation, the diaphragm may preferably be retracted tosolid line position and table 19 lowered to remove the flask and moldfrom box 50 and then to draw pattern P.

In FIGS. 9 and 10 there is illustrated a related modification likewiseproviding for blowing of the sand into the flask and girdle butcombining certain aspects of the previously described embodiments toachieve superior results.

The lower end of reservoir 39 in this case has an especial adapter 57secured thereto terminating in central blow opening 58. An annulardiaphragm 59 somewhat similar to diaphragm 45 (FIG. 7) is secured to theunderside of the adapter by outer clamping ring 68 and inner ring andspreader 61 which also serves to distribute the sand discharged fromblow opening 58. No vents are provided of the usual type, special meansbeing employed for this purpose. A filler opening 612 permits the spaceabove diaphragm 59 to be filled with fluid, preferably hydraulic fluid,and such opening is then closed with plug 63 so that while theconformation of the diaphragm 59 may be altered by flexing, the totalspace occupied by the cavity behind the diaphragm is substantiallyunalterable. Accordingly, if such diaphragm is caused to protrude in oneportion, it must be correspondingly retracted in another portion, andvice versa.

The girdle proper 64 is quite similar to girdle 2L7 (FiG. 3) and issimilarly provided with a generally cylindrical diaphragm 65 securedtherewithin at its upper and lower edges and adapted to surround theflask F and pattern P when these have been elevated into position withinthe girdle as shown in FIG. 9.

A ring 65 is mounted on the upper end of girdle 64 and forms an upperextension of the same dimensioned to clear the lower margin of adapter57 with only slight space therebetween. Ring 66 and girdle 64 aresuspended from upper flange 57 of the adapter by means of bolts such as63 passing through outwardly projecting flange 69 on ring as.Compression springs such as 7%? are interposed between flanges 67 and 69tending (in conjunction with gravity) to hold girdle 64 in its lowermostposition as shown in FIG. 9. This is the blow position.

An annular brush element '71 having brush material '72 projectinginwardly is mounted on flange 6) of ring us with the brush face (i.e.the inner ends of the brush material 72) engaging the outer surface ofclamping ring 68 and adapter 57. Air is enabled to filter outwardlythrough such brush material during performance of the blowing operation,thereby affording superior venting means. Furthermore, girdle 6d andring 66 may be reciprocated vertically relative to adapter 57 withoutdisturbing such venting means.

The operation of this embodiment of the invention may now be understoodin conjunction with a consideration of FIG. 10. As above indicated,squeeze table 19 is elevated first to pick up flask F and then to carrythe latter into girdle 64, making sealing engagement with the lower lipof the latter as shown in FIG. 9. The blowing operation is thenperformed to fill girdle 64 and ring as, which thus serves as an upsetframe similar to frame 32, diaphragm 65 being in retracted position asshown in FIG. 9. Squeeze table 1) is next further elevated asillustratedin FIG. 19 with consequent compression of springs 70 andreciprocation of brush 72 along the outer surface of clamping ring 69and adapter 57. Inasmuch as the fluid behind diaphragm 59 issubstantially incompressible and cannot escape from the cavity, the sandis firmly squeezed thereagainst and also against the central portion ofthe sand distributing nozzle 61. Diaphragm being flexible, is capable ofaltering its contour to accommodate portions of the flask grid bars 38.Simultaneously with or immediately following such squeezing operation,fluid under pressure is admitted through inlet 73 in girdle 64 toinflate diaphragm 65, thereby also compacting the sand peripheries ofpattern P. It will thus be seen that I provide for mechanicallysqueezing the sand within the girdle by further elevation of the flask,pattern and girdle to press the sand against a deformable butincompressible squeeze head, while actively exerting a squeezingpressure laterally of the pattern by means of expansible diaphragm 65.The advantages of the upper diaphragm squeeze are obtained with thesimplicity and power of the already available piston-cylinder assembly18, 17. The diaphragm 65 is then retracted to FIG. 9 position, and table19 lowered todrop the girdle to FIG. 9 position and then to carry theflask and mold downwardly out of the girdle followed by drawing of thepattern from the flask.

It will be apparent from the foregoing description that my new flask isan important element of the cooperative assembly making feasible the newmethod of molding. Obviously, the usual foundry flasks, even thoseprovided with large vent openings, would be unsuitable for my purposeinasmuch as they would not permit adequate lateral squeezing of the sandagainst the pattern and would themselves be damaged and deformed by anysuch squeezing operation. The details of construction of a preferredembodiment of my new flask are shownin FIGS. 11-14 inclusive of thedrawing. The main frame of the flask may comprise a horizontal plate orflange having a large central opening bridged by arched frame members 38welded thereto. Such frame members extend at right angles to one anothernormal to the respective side edges of flange 24, thereby forming ahorizontal grid on that side which is normally uppermost duringperformance of the molding operation. The bars 3% may be of generallyelongated cross-section with their inner and outer edge portionsbevelled as shown in FIG. 14, such bevelling facilitating intrusion ofsand into the interior of the flask during the filling and squeezingoperations and also assisting in holding the sand of the completed mold.Similarly, the double bevelled apertures 5d which are provided atintervals through bars 38, when filled with sand during the moldingprocess, assist in locking the completed mold within the flask.Horizontal rods may be inserted through certain sets of alignedapertures 55, particularly in the upstanding leg portions of bars 38 toform side grids therewith better to support the finished mold. Theprecise number and location of such supplemental rods 56 will depend onthe particular pattern and composition of molding material beingemployed. While the flask is thus of general skeleton grid construction,it nevertheless rigidly reinforces and protects the completed mold andmay be handled in generally the same manner as conventional flasks. Costof fabrication of these flasks is reasonable, and only the lower flange24 is required to mate with opposed supporting and/ or clampingsurfaces. The grid construction much facilitates shake-out after pouringand solidification of the castings.

My new skeleton flask need not always have the grid top shown,particularly in the smaller sizes, but it will ordinarily be desirableto provide at least several crossbars in this region. The openings inthe sides of the flask must be large and closely spaced to afford aminimum of resistance to the circumferential, laterally inward squeezingaction of the encircling diaphragm. Thus, such openings will ordinarilybe at least 4 or 5 inches wide in their narrowest dimension. The flaskneed not be of general rectangular form as shown but may be of irregularshape to conform generally to the contours of a particular pattern,thereby saving weight and reducing the amount of molding sand which needbe employed. In some few cases, the lateral squeeze applied by theencircling diaphragm may be sufficient to form a satisfactory moldwithout further squeezing of the sand against the top of the pattern.This is particularly true when the sand has been deposited against thepattern by a blowing operation, such operation tending to compact thesand particularly firmly against the upper surfaces of the patterngenerally opposed to the blow hole. In some cases, it may be feasible todispense with the flask entirely and, after with drawing the mold fromthe girdle frame, placing such mold in a pouring flask prior to pouringthe metal therein. The girdle frame is desirably of downwardly outwardlyflaring conformation as shown to facilitate withdrawing the moldtherefrom.

While an important advantage of my invention is that under mostcircumstances there is no need to jolt in order to compact the sandproperly uniformly against the pattern surfaces, nevertheless it will beobvious that a supplemental jolting operation may be utilized ifdesired, prior to performing the squeeze operation (prior to shiftingthe flask and girdle upwardly against the squeeze head in the FIG. 1 andFIG. 9 embodiments). Of course, the squeezing operation may be directlyagainst the squeeze head adapter in the FIG. 9 embodiment withoututilizing the upper diaphragm 59, although the latter is much preferred.Likewise, such upper diaphragm 5% may be inflated and deflated similarlyto diaphragm 45 in FIG. 7 instead of or in addition to the applicationof squeezing pressure through further elevation of table 19. It willlikewise be obvious that instead of employing a single continuousdiaphragm encircling the flask within the girdle frame severalindividual diaphragms may be utilized located where most needed withrespect to the particular pattern. The diaphragm arrangement shown inFIG. 8 is, however, ordinarily superior and preferred.

Other modes of applying the principle of the invention may be employed,change being made as regards the details described, provided thefeatures stated in any of the following claims or the equivalent of suchbe employed.

I therefore particularly point out and distinctly claim as my invention:

1. In a foundry molding machine having a vertically reciprocable squeezetable adapted to support a flask and pattern thereon, and a squeeze headadapted to engage and squeeze sand within such flask when said table iselevated; a skeleton flask on said table having large closely spacedopenings in its sides, a girdle frame adapted temporarily to enclosesaid flask on said table for filling with molding sand, and lateralsqueeze means within said girdle frame operative to squeeze sand againstside faces of such pattern within said flask.

2. The machine of claim 1, wherein said lateral squeeze means is aflexible diaphragm adapted to be forced inwardly by fluid pressureintroduced therebehind.

3. The machine of claim 1, wherein said lateral squeeze means is aflexible diaphragm adapted to be forced inwardly by fluid pressureintroduced therebehind, said diaphragm completely encircling said flaskwithin said girdle means.

4. The machine of claim 1, wherein said flask corn prises a grid ofclosely spaced wide openings at its upper side, and said squeeze head isprovided with a plurality of downwardly extending squeeze biscuitsadapted to project through such latter openings.

5. The machine of claim 1, wherein said squeeze head is provided at itsunderside with a fluid backed downwardly bulging flexible diaphragmadapted to engage and compact sand in said flask when said table isfully elevated.

6. The machine of claim 1, including an upwardly extending upset frameportion on said girdle frame adapted to receive additional sand prior toperformance of the squeezing operations.

7. In a molding machine comprising a flask and pattern supporting table,a mold blowing machine having a downwardly opening box with a centrallydisposed blow hole in the top of said box, and power means operative toraise and lower said table to carry such flask and pattern into said boxand to withdraw them and the mold from said box; a skeleton flask onsaid table having large closely spaced openings in its sides, lateralsqueeze means within said box operative to squeeze sand against sidefaces of such pattern within said flask, and a flexible diaphragm in theupper part of said box adapted to be forcibly bulged downwardly byintroduction of fluid pressure therebehind to compact sand against uppersurfaces of such pattern.

8. The machine of claim 7, wherein said diaphragm is annular andsurrounds such blow hole.

9. The machine of claim 7, wherein said lateral squeeze means is aflexible diaphragm adapted to be forced inwardly by fluid pressureintroduced therebehind.

10. The machine of claim 7, wherein said lateral squeeze means is aflexible diaphragm adapted to be forced inwardly by fluid pressureintroduced therebehind, said latter diaphragm completely encircling saidflask within said box.

11. In a molding machine comprising a flask and pattern supportingtable, a mold blowing machine having a downwardly opening box with acentrally disposed blow hole in the top of said box, and power meansoperative to raise and lower said table to carry such flask and patterninto said box and to withdraw them and the mold from said box; askeleton flask on said table having large closely spaced openings in itssides, and squeeze means within said box comprising a flexible diaphragmencircling said flask and overlying the upper portion thereofcircumferentially of such blow hole adapted to squeeze sand against bothupper and lateral surfaces of such pattern upon introduction of fluidpressure therebehind.

12. A molding machine comprising a flask and pattern supporting squeezetable, a mold blowing machine having a blow hole generally centrallyabove said table, a squeeze head surrounding such blow hole, a skeletonflask on said table having large closely spaced openings in its sides, agirdle frame adapted temporarily to enclose said flask on said table forfilling with molding sand, lateral squeeze means within said girdleframe operative to squeeze sand against side faces of such patternwithin said flask, and power means operative to lift said table tosqueeze sand within said girdle frame against said squeeze head tocompact such sand against the upper surface of such pattern.

13. The machine of claim 12, wherein said lateral squeeze means is aflexible diaphragm adapted to be forced inwardly by fluid pressureintroduced therebehind.

14. The machine of claim 12, wherein said squeeze head is provided atits underside with a fluid backed downwardly bulging flexible diaphragmadapted to engage and compact sand in said flask when said table isfully elevated.

15. The machine of claim 12, wherein said lateral squeeze means is aflexible diaphragm adapted to be forced inwardly by fluid pressureintroduced therebehind. said diaphragm completely encircling said flaskwithin said girdle means, and said squeeze head is provided at itsunderside with an annular downwardly bulging flexible diaphragm backedby substantially incompressible fluid sealed therebehind, said latterdiaphragm encircling such blow hole, said girdle frame being of widerdimensions than said squeeze head for relative vertical reciprocationwhen squeezing such sand against said downwardly bulging diaphragm.

16. The machine of claim 12, wherein such blow hole is directedlaterally to expose a substantially central area of said squeeze headfor squeezing action on sand in said girdle frame.

17. The machine of claim 12, wherein said girdle frame is of widerdimensions than said squeeze head for relative vertical reciprocationwhen squeezing such sand against said squeeze head.

18. The machine of claim 12, wherein said girdle frame is of widerdimensions than said squeeze head for relative vertical reciprocationwhen squeezing such sand against said squeeze head, and venting meansfor the blowing operation are provided between the outer lateral surfaceof said squeeze head and the inner surface of said girdle frame.

19. The machine of claim 12, wherein said girdle frame is of widerdimensions than said squeeze head for relative vertical reciprocationwhen squeezing such sand against said squeeze head, and venting meansfor the blowing operation are provided between the outer lateral surfaceof said squeeze head and the inner surface of said girdle frame, saidventing means comprising brush bristle material closing the spacebetween said squeeze head and A! girdle frame but adapted to allow thepassage of high pressure air therethrough while preventing passage ofsand particles.

20. A molding machine comprising a flask and pattern supporting squeezetable, a mold blowing machine having a blow hole generally centrallyabove said table, a squeeze head surrounding such blow hole provided atits underside with an annular downwardly bulging flexible diaphragmbacked by substantially incompressible fluid sealed therebehind, saiddiaphragm encircling such hole, a skeleton flask on said table havinglarge closely spaced openings in its sides, a downwardly flaring girdleframe adapted temporarily to enclose said flask on said table forfilling with sand, lateral squeeze means mounted within said girdleframe comprising a flexible diaphragm encircling said flask and adaptedto be forced inwardly by fluid pressure introduced therebehind, saidgirdle frame being of wider dimensions than said squeeze head forrelative vertical reciprocation when squeezing such sand against saiddownwardly bulging diaphragm, brush bristle material closing the spacebetween said squeeze head and girdle frame adapted to vent high pressureair therethrough while preventing passage of said particles, supportmeans suspending said girdle frame from said blowing machine forvertical reciprocation relative to said squeeze head, and power meansoperative to lift said table and girdle frame to squeeze sand withinsaid girdle frame against said downwardly bulging diaphragm to compactsuch sand against the upper surface of such pattern and to lower saidtable to withdraw the pattern and mold from said girdle frame.

21. The machine of claim 20, including means adapted to stop downwardmovement of said flask to cause drawing of the pattern from the moldupon further lowering of said table, a grid forming the upper side ofsaid flask, an upset frame portion on said girdle frame adapted toreceive additional sand from the blowing operation prior to performanceof the squeezing operations, and spring means urging said girdle framedownwardly to lowermost suspended position, said blow hole being dividedand turned laterally to expose a substantial area of said squeeze headcentrally of said annular downwardly bulging diaphragm for squeezingaction on such sand within said girdle frame.

22. The method of forming a mold which comprises blowing molding sandinto a box containing a pattern, then squeezing such sandcircumferentially inwardly against the sides of such pattern,withdrawing the resultant mold and pattern from such box, and drawingsuch pattern from such mold.

23. In the method of claim 22, also squeezing such sand against the topof such pattern.

24. The method of forming a mold which comprises depositing molding sandagainst a pattern in a box, then squeezing such sand laterally inwardlyagainst such pattern, lifting such pattern and box to squeeze the upperportion of such sand against a squeeze head to compact such sand againstthe top of such pattern, withdrawing the resultant mold and pattern fromsuch box, and drawing such pattern from such mold.

25. The method of forming a mold which comprises placing a patternwithin a skeleton flask, placing such pattern and flask within anencircling enclosure, filling such enclosure and flask with moldingsand, applying squeezing pressure on such sand from outside the confinesof such flask to compact such sand against such pattern and form a moldbody interengaged with such skeleton flask, withdrawing such flask, moldand pattern from such enclosure, and drawing such pattern from suchmold.

26. In the method of claim 25, applying squeezing pressure on such sandlaterally of such pattern from outside the confines of such flask.

27. In the method of claim 25, applving squeezing pressure on such sandlaterally of such pattern from out- 19 side the confines of such flaskand also generally vertically downwardly theretoward.

28. The method of forming a mold which comprises placing a patternwithin a skeleton flask, squeezing sand against such pattern by pressureapplied from laterally outside the confines of such flask acting throughopenings in the sides of such flask, and drawing such pattern from theresultant mold.

29. The method of claim 28, including also squeezing such sand againstthe top of such pattern.

30. In a foundry molding machine, a support, a skeleton flask on saidsupport, an enclosing frame encircling said flask adapted to containmolding sand therein, squeeze means operative to compact sand withinsaid frame to form a mold in interengagement with said skeleton flask,and means for withdrawing said flask and mold as a unit from said frame.

31. A skeleton foundry molding flask comprising a horizontal flatrectangular base flange, a plurality of arched frame members havingtheir ends mounted on said flange at opposite sides of such rectangleand together forming a grid where they cross one another, said framemembers being of narrow cross-section in the lengthwise direction of thearch and tapered edgewise to afford small resistance to inward flow ofsand therepast, said frame members having series of aligned aperturestherethrough, and rods removably inserted in certain of said series ofapertures parallel to said base flange.

32. The flask of claim 31, in which said frame members are thus taperedboth outwardly and inwardly, and certain of said apertures are leftunobstructed for interengagement with compacted molding sand.

33. In a mold blowing machine operative to blow molding sand against apattern within a box and having a portion of said machine closing theupper side of said box, means operative to elevate said box and patternto squeeze such sand against said portion of said machine, and a sealbetween the upper portion of said box and said portion of said machineadapted to vent air under pressure therethrough but restrain passage ofsand, wherein said seal comprises brush means.

34. In a foundry molding machine, vertical squeeze means operative tocompact molding sand against the top of a pattern and horizontal squeezemeans operative to compact molding sand against a side of such pattern,and a skeleton flask enclosing such pattern, said horizontal squeezemeans being located laterally outside said flask.

35. In a mold blowing machine operative to blow molding sand against apattern within a box, a squeeze head having an opening therethrough, asqueeze table mounted for reciprocation toward and away from saidsqueeze head, a pattern enclosing shell supported on said table andhaving upper marginal dimensions slightly greater than the correspondingdimensions of said squeeze head to permit reciprocation of said uppermargin of said shell past said squeeze head, means operative to blowsand through said opening into said shell, and means operative toreciprocate said table and shell relative to said squeeze head furtherto compress such sand against such pattern, and a lateral sliding sealprovided between said squeeze head and said shell, said seal being ofbristle material to vent air during such blowing operation whilepreventing escape of sand.

36. In a mold blowing machine operative to blow molding sand against apattern within a box, a squeeze head having an opening therethrough, asqueeze table mounted for reciprocation toward and away from saidsqueeze head, a pattern enclosure supported on said table, meansoperative to blow sand through said opening against such pattern withinsaid enclosure, such opening being provided with a deflector portioneffective laterally to direct such sand blown through such opening, andmeans operative to reciprocate said table to squeeze such sand withinsaid enclosure against said squeeze head and deflector, said deflectorthus being disposed to protect 1 1 such blow opening and any sandtherein from such squeeze pressure.

37. In a foundry molding machine having a vertically reciprocablesqueeze table adapted to support a flask and pattern thereon, and asqueeze head adapted to engage and squeeze sand within such flask whensaid table is elevated; a generally centrally disposed verticallyextending blow opening in said head terminating in a sand spreaderunderlying such opening adapted laterally to distribute sand dischargedfrom such blow opening into such flask against such pattern; and a fluidbacked flexible diaphragm mounted on the underside of said squeeze headlaterally of such blow hole, said diaphragm and spreader being adaptedjointly to engage and compact the sand within such flask when said tableis further elevated, said deflector thus protecting such blow openingand any sand therein from such compacting pressure.

38. In a mold blowing machine operative to blow molding sand against apattern within a box, a squeeze i head having an opening therethrough, asqueeze table mounted for reciprocation toward and away from saidsqueez'head, a pattern enclosure supported on said table and havingupper marginal dimensions slightly greater than the correspondingdimensions of said squeeze head to enable reciprocation of said uppermargin of said enclosure vertically past said squeeze head, meansoperative to blow sand through such opening into said enclosure, andmeans operative to reciprocate said table and enclosure relative to saidsqueeze head further to compress such sand against such pattern, alateral sliding porous seal being provided between said squeeze head andsaid enclosure to vent air during such blowing operation whileeffectively preventing escape of sand from said enclosure.

39. In a foundry molding machine having a squeeze head and flasksupporting table mounted for relative vertical reciprocation, powermeans for effecting such reciprocation, a pattern on said table, and abox carried by said table and encompassing said pattern; a fluid backedflexible diaphragm mounted on the underside of said squeeze head andsecured to a relatively rigid downwardly projecting peripheral marginportion of the latter, said peripheral margin portion of said squeezehead being dimensioned to fit within said box for relative verticalreciprocation to squeeze sand within said box against said pattern,whereby the laterally outer portion of such sand in said box may besqueezed directly against said rigid downwardly projecting peripheralmargin portion of said squeeze head and the mounting of said diaphragm12 may be moved progressively nearer said pattern as the squeezingoperation proceeds.

40. The machine of claim 39, wherein said box is provided with an upwardextension in the form of a similarly'dimensioned fill frame adapted thusto receive said squeeze head.

41. The machine of claim 39, wherein said squeeze head is provided witha blow opening for blowing sand therethrough into said box against saidpattern prior to such squeezing operation.

42. In a foundry molding machine, a downwardly opening box adapted toenclose a pattern covered by molding sand; a flexible diaphragm securedat its edges within said box and extending circumferentially of the sandwithin said box, and means for applying fluid pressure behind saiddiaphragm to force the latter inwardly to squeeze the sand against saidpattern; the same diaphragm also extending a substantial distance overthe upper part of the sand so that the sand may simultaneously besqueezed downwardly against said pattern thereby.

43. In a foundry molding machine, a downwardly opening box adapted tocontain a pattern covered With molding sand; a flexible diaphragmsecured at its upper and lower edges within said box and extendingcircumferentially of said box around such pattern and sand, saiddiaphragm being adapted to be forced inwardly to squeeze such sandcompletely circumferentially against such pattern upon introduction offluid pressure therebehind, and said diaphragm being disposed also tooverlie a portion of the upper surface of such pattern and sand.

References Cited in the file of this patent V UNITED STATES PATENTS302,349

Moore July 22, 1884 318,784 Moore May 26, 1885 331,208 Moore Nov. 24,1885 505,155 Bradbury Sept. 19, 1893 752,797 Norcross Feb. 23, 1894993,953 Buch May 30, 1911 1,544,216 Campbell June 30, 1925 2,127,204Daniel Aug. 16, 1938 2,698,976 Taccone Jan. 11, 1955 2,757,424 Daniel etal. Aug. 7, 1956 2,791,013 Demmler May 7, 1957 2,839,799 Herbruggen June24, 1958 2,864,136 Taccone Dec. 16, 1958 FOREIGN PATENTS 2,467 GreatBritain July 8, 1875

1. IN A FOUNDRY MOLDING MACHINE HAVING A VERTICALLY RECIPROCABLE SQUEEZETABLE ADAPTED TO SUPPORT A FLASK AND PATTERN THEREON, AND A SQUEEZE HEADADAPTED TO ENGAGE AND SQUEEZE SAID WITHIN SUCH FLASK WHEN SAID TABLE ISELEVATED; A SKELETON FLASK ON SAID TABLE HAVING LARGE CLOSELY SPACEDOPENINGS IN ITS SIDES, A GIRDLE FRAME ADAPTED TEMPORARILY TO ENCLOSESAID FLASK ON SAID TABLE FOR FILLING WITH MOLDING SAND, AND LATERALSQUEEZE MEANS WITHIN SAID GIRDLE FRAME OPERATIVE TO SQUEEZE SAND AGAINSTSIDE FACES OF SUCH PATTERN WITHIN SAID FLASK.
 22. THE METHOD OF FORMINGA MOLD WHICH COMPRISES BLOWING MOLDING SAND INTO A BOX CONTAINING APATTERN, THEN SQUEEZING SUCH SAND CIRCUMFERENTIALLY INWARDLY AGAINST THESIDES OF SUCH PATTERN, WITHDRAWING THE RESULTANT MOLD AND PATTERN FROMSUCH BOX, AND DRAWING SUCH PATTERN FROM SUCH MOLD.